Question

What will be proper way to catch exception which throw SQL server when I deleting data with Reference constraint from C# code.
I want to show my users message like:
“I can’t delete the data because is used”
, rather than of showing message like this:

The DELETE statement conflicted with the REFERENCE constraint ... The conflict ccurred*in database "rampa", table "dbo.doc", column 'kartica_id'.

Answer 1

Use this:

try
{
   //Execute delete statement
}
catch (SqlException sqlEx)
{
   //Handle exception
}
finally
{
   //Close connection
}

All sql errors are thrown as SqlException and there are no specific errors. To find out what was error exactly, there is property SqlException.Number which is the same as SQL Error Code. You can find the list of codes here.